It also has an effect on:
secretion and regulation of insulin by your pancreas
heart and blood pressure regulation
Pretty important stuff.
A few weeks ago, the British Medical Journal published a remarkable paper – remarkable that it studied more than 500,000 subjects, remarkable that it had 56 (fifty-six) authors, remarkable that it confirmed low vitamin D levels obtained in the past are a risk factor for developing colon cancer in the future…
However, the most remarkable part of the paper is that the 56 scientists minimized the true significance of their own research. They found that vitamin A, EVEN IN RELATIVELY LOW AMOUNTS, appears to thwart vitamin D’s association with reduced rates of colon cancer. …also the paper notes that alcohol thwarts the effects of vitamin D as well.
Hidden on page eight of the paper is one sentence and a small table, which shows that the benefits of vitamin D are almost entirely negated in those with the highest vitamin A intake. And the retinol intake did not have to be that high in these older adults to begin to negate vitamin D’s effects, about 3,000 IU/day, which is contained in many multi vitamins and in cod liver oil.
Naturally, vitamin A production is tightly controlled in your body. The substrate of the vitamin A, are carotenoids from vegetables in your intestine. Your body converts these carotenoid substrates to exactly the right amount of retinol. However, when you take vitamin A as retinol directly, such as in cod liver oil, you bypass all the natural controls in this closed system.
Ideally, youâ??ll want to provide all the vitamin A and vitamin D substrate your body needs in such a way that your body can regulate both systems naturally.
This is best done by eating colorful vegetables (for vitamin A) and by exposing your skin to sun every day (for vitamin D).
Interaction with Calcium: Also the study showed that higher intake of dietary calcium showed some evidence of association with a reduced cancer risk association, particularly in the rectal anatomical sub-site.
What you can do?
- Obviously don’t take a multi with retinol, rather obtain Vit A substrates from whole foods, or a multi that has natural caretenoids in it.
- Also avoid or limit alcohol intake
- Ensure adequate calcium is obtained
- Ensure adequate Vit D from sun, supplement, and or food combo.
- Test Vit D levels